Drilling mechanism



Feb. 27, 1934. E. G. GARTIN DRILLING MECHANISM Filed March 10, 1950 2 Sheets-Sheet l lrvvsn'Ton: ELMEHGZGHRTl/Y. BY

HTT'K Patented Feb. 27, 1934 UNITED STATES DRILLING MECHANISM Elmer G. Gartin, Claremont, N. H., assignor to Sullivan Machinery Company, a corporation of Massachusetts Application March 10, 1930. Serial No. 434,650

13 Claims.

This invention relates to drilling mechanisms and more particularly to an improved feeding means and arrangement therefor especially adapted to the drifter type. of hammer drill provided with motor actuated feeding mechanism.

In drilling holes with a hammer type drilling mechanism employing usual steel rotating mechanism such as the pawl and ratchet and rifle bar construction orindependent rotation motor, it is desirable to have the steel disposed slightly away from or only slightly against the bottom of the hole during rotation of the steel for otherwise the cutting edges of the steel if held in contact with the bottom of the hole will be dulled or ground down during rotation. To permit relatively free rotation of the steel various methods have heretofore been employed in connection with the drill steel. feeding and rotating means. In: such prior devices where a feed screw is used yieldable means are usually interposed in the feed train but these have certain disadvantages and also do not have that degree of resiliency or flexibility of operation such as is obtained with a fluid pressure feed cylinder. herently has the desirable characteristic of permitting the drill and steel to rebound from the bottom of the hole during which time the drill is rotated. and of also permitting the feeding power to constantly urge or bias the drilling motor forward even during rebound, yet it has the disadvantage of being relatively heavy and expensive to manufacture.

It is an object of my invention to provide an improved feeding arrangement whereby the desirable characteristics of a fluid pressure and mechanical feed may be obtained without incurring the many undesirable features of each. A further and more specific object of the invention is to provide an improved feeding arrangement whereby the rebound may be absorbed directly by the motor of-whatever type is employed and which at the same time will constantly urge or bias the drill in a feeding direction preferably under a fiuid feeding force, notwithstanding the rebound. Another object is to provide an improved arrangement of parts whereby a relatively simple structure is obtained and which will have a high degree of flexibility and ease of operation and will be relatively inexpensive both in its manufacture and maintenance. A further and more specific object of my invention is to provide improved feeding mechanism which does not require a feed screw and yet will permit the use of fluid pressure power medium constantly acting to effect feeding without the use of a feed piston and cylinder as heretofore employed. A fur ther and more specific object is to provide a fluid operated motor carried preferably by the While a fluid feed cylinder inrear head of the drilling mechanism and so arranged as to obtain a relatively simple feed gear train for driving a rotatable element along a cooperating member which has its ends and intermediate portions held against movement such for instance as a flexible cable or a gear rack.

Further objects and advantages will be readily understood from the following description of the accompanying drawings in which,--

Fig. l is a plan view of one form of my improved mechanism associated with an approved drifter type of drill mechanism.

Fig. 2 is an enlarged transverse sectional view taken substantially on line 2--2 of Fig. 1.

Fig. 3 is an enlarged sectional view taken substantially on line 3-3 of Fig. 2.

Fig. 4 is an enlarged vertical section taken on line 4+4 of Fig. 2.

Fig. 5 is a transverse vertical section taken through the motor mechanism of a modified.

form of the invention.

Fig. 6 is a fragmentary vertical transverse section taken on the line 6-6 of Fig. 7, which is a further modified form. f

Fig. 7 is a transverse horizontal section taken substantially on the line '7-7 of Fig. 6.

Fig. 8 is a fragmentary vertical sectional view of a still further modified form.

The illustrative embodiment of my invention is shown in connection with a drifter type of drilling mechanism having a fluid pressure operated hammer motor 1, of a usual form, provided at its front end with the usual chuck 2 for receiving a drill steel 3, while the rear end is provided with a usual rear head 4 carrying the throttle valve 5 for controlling actuating fluid to the hammer motor. There is provided also a shell 6 adapted to slidably guide the drilling mechanism longitudinally thereof as by gibs 7, 7 carried on the under side of the drilling motor and receivable in usual guideways 8. A usual trunnion 9 is disposed preferably centrally of the shell while in the preferred form of my invention the shell also has a relatively narrow longitudinal channel 10 in one side of which is disposed a rack 11. To feed the drilling mechanism along the guideways 8 there is provided a feeding motor, generally indicated at 12, carried by and secured to the rear head 4 either by bolts or by being formed integrally therewith.

In one specific aspect of my invention the motor is of the fluid actuated intermeshing toothed rotor type having rotors l3 and 14 rotatable about vertical axes, it being noted, as shown in Fig. 2, that a shaft 15 is keyed to its rotor while the lower end of said shaft carries a pinion 16 meshing with and driving a gear 1'7 keyed to a vertical shaft 18 which carries a pinion 19 meshing with the rack 11. The shaft 18 is suitably journaled in a lower cover 20 of the motor casing and is so arranged that a portion thereof projects downwardly between the guideways 8 thus permitting the feeding motor to be disposed relatively close to the shell to provide a compact arrangement.

To control the supply of actuating fluid to the feed motor either simultaneously with, or independently of. operation of the drilling motor there is provided a separate feed control valve 21 having its supply passage connected as by pipe 22 to asupply 23 common with the drilling motor throttle valve 5. Suitable and usual handles are provided for each of the valves 5 and 21. To permit forward or reverse feed, valve 21 is, as shown in Fig. 4, provided with an inlet port 24 and exhaust groove 25 communicating respectively with passages 26 and 27 leading respectively to opposite sides of the rotors as shown in Fig. 3. By turning valve 21 through approximately 90 the supply and exhaust of fluid from the opposite sides of the rotors may be reversed thereby effecting reverse feed.

The operation of this preferred arrangement is believed to be obvious in that the drilling mechanism may be fed forwardly merely by manipulating the valve 21 and upon engagement of the steel with the face of the material, throt tle valve 5 may be opened whereby the drilling motor 1 will then impart a series of blows to the drill steel. As is well known and understood, the steel is rotated during operation of the drilling motor as through any usual steel rotation mechanism.

From the foregoing description of this form of my improved arrangement it is seen that any rebound which may occur due to the operation of the drilling motor will be transmitted back to and absorbed by the motor which, even without the interposition of any loose or yieldable connections, will permit sufiicient yielding dur ing the rebound to permit effective steel rotation and yet immediately upon absorption of this rebound the drilling mechanism is fed forward, this being due to the constant effort or feeding force which is applied directly from the motor to the feeding rack 11. It is thus seen that the rebound is absorbed directly by the gear teeth of the feeding motor rotors which in turn are reacting against the constant supply of fluid pressure. It is by this improved arrangement that I have been able to obtain all the desirable feeding characteristics of the pneumatic and mechanical feeds without incurring many of the disadvantages of each.

The above desirable advantages are also obtained in the modified arrangement shown in Fig. 5 wherein the feeding motor generally indicated at 28 is disposed with the motor rotor axes horizontal and each lying in a common vertical plane with the lower rotor shaft 29 extending outwardly through each side of the casing to carry pinions 30, 31 engaging racks 32, 33. The arrangement as shown thus provides an equalized feeding force to each side of the shell and also equalizes the stresses on the feeding motor. It also will be noted that the arrangement here shown has the feeding motor disposed well within the shell 34. The remaining structure of the drilling mechanism shell and actuating fluid control valves is generally the same as that shown in the preferred form.

In the modified form shown in Figs, 6 and 7,

instead of rack and pinions, small pulleys 35 substituted for the pinions 30, 31, each cooperate with a flexible member 36 such as a rope or cable. The flexible member is given a few turns around each pulley and is preferably fixed at one end 37 in any suitable manner while the other ends are preferably yieldably supported against the tension of a compression spring 38 thereby maintaining uniform frictional engagement between each of the flexible members and their respective pulleys. It is also to be noted that if some abnormal condition should arise necessitating slippage of the feed, the flexible members and their pulleys could provide the necessary slippage therebetween, this being varied or entirely eliminated as desired in accordance with the tension of the flexible members.

In the further modified form shown in Figure 8 there is provided a single flexible member 40 wrapped around a pulley 41 secured to a vertical shaft 42. The shaft 42 corresponds to shaft 18 in the preferred form and the arrangement of the feed motor with the gear reduction shown is the same as in the preferred form.

It is thus seen that in all of the forms shown the desirable advantages previously outlined are obtained and in addition, when the feed control valve 21, which is used for all forms, is in its neutral position so as to exhaust fluid from both sides of the rotors, the drilling mechanism may be freely moved in either direction by hand thus avoiding the necessity for releasable nuts or other members which are common to mechanical feeds.

While I have in this application specifically described one form and modifications thereof which the invention may assume in practice, it will be understood that this form and modifications of the same are shown for purposes of illustration and that the invention may be modified and embodied in various other forms without departing from its spirit or the scope of the appended claims.

What I claim as new and desire to secure by Letters Patent is:

1. A drilling mechanism comprising, in com bination, a drilling motor, means for slidably guiding and supporting the same, and yielding resilient feeding mechanism for said drilling motor including a fluid actuated intermeshing rotor type of motor, and constantly engaged power transmission mechanism driven by said feed motor adapted, while its connection with said feed motor is maintained, to permit the drilling motor to be moved by hand along its guide while said transmission mechanism is in its normally constant egaging relation.

2. A drilling mechanism comprising, in combination, a shell, a drilling motor slidably supported and guided thereby, and yielding resilient feeding mechanism for said drilling motor including a feed motor having a rotor, a rack carried by said shell, and a gear train between said feed motor and rack in constant driving relation and adapted, while its connection with said feed motor is maintained, during said relation and when power supply to said motor is shut off, to permit free movement of the drilling motor by hand.

3. A drilling mechanism comprising, in combination, a shell, a percussive drilling motor slidably guided and supported thereby, yielding resilient feeding mechanism for said drilling motor including a feed motor having a fluid actuated power rotor, a feed engaging member carried by said shell, and driving connections between said motor and member including an element engageable with said member to be moved along the same, said driving connections being adapted during their normal driving relation, while its connection with said feed motor ismaintained, to permit free movement of the drilling motor in either direction.

4. A drilling mechanism comprising a shell, a percussive drilling motor slidably guidedand supported thereby, yielding resilient feeding mechanism for said drilling motor including a feed motor having a power rotor rotatable on its own axis but held against movement longitudinally of the latter, and means whereby said feed motor constantly exerts a feeding force on said drilling motor while permitting, and irrespective of, movement of the drilling motor.

5. A drilling mechanism comprising, in combination, a shell, apercussive drilling motor slidably guided and supported thereby, and feeding means for said drilling motor including a fluid actuated plural rotor type'motor, a feed engaging member carried by said shell, a spur tooth pinion carried by one of said rotors and spur tooth driving connections between said pinion and said feed engaging member whereby said motor and engaging member are constantly in their normal driving relation throughout all movements of said drilling motor.

6. A drilling mechanism comprising in combinationa shell, a percussive drilling motor slidably guided and supported thereby and yielding resilient feeding means for said drilling motor including a reversible fluid operated motor carried by said drilling motor, a feed engaging member carried by said shell and normally fixed against movement between its ends, and constantly operative connections between said motor and engaging member adapted at all times to. exert a feeding force on said drilling motor whenever power is supplied to the said feeding motor for effecting movement in either direction and permitting free movement of the drilling motor when power supply to said feed motor is cut off. I

7. A drilling mechanism comprising, in combination, a shell, a percussive drilling motor slidably guided and supported thereby, yielding resilient feeding means for said motor including a fluid actuated feed motor, a feed engaging member fixed to and carried byvsaid shell, constantly operative driving connections including relatively rotatable power transmitting members between said feed motor and engaging member and one engaging and coacting with the former and another with the latter for exerting a constant feeding force on said drilling motor at all times during operation of said percussive drilling motor, and means adapted to control the supply of actuating fiuid to said drilling and feed motors independently of each other, said driving connections permitting free movement of said drilling motor relative to said shell in either direction when the supply of fluid to the feed motor is cut oil".

8. The combination set forth in claim '7 further characterized in that the means for controlling supply of actuating fluid to said motors may permit supply simultaneously to each.

9. A drilling mechanism comprising, in combination, a guide shell, a percussive drilling motor slidably guided and supported by said shell, and feeding means for said drilling motor ineluding a fluid actuated feed motor having a rotating element and means for maintaining a torque thereon during fluid supply to said motor, a feed engaging member carried by said shell, a spur toothed pinion carried by the rotating element of said feed motor, and spur toothed driving connections between said pinion and said feed engaging member whereby said feed motor and engaging member are constantly in their normal driving relation throughout all movements of said drilling motor.

10. A drilling mechanism comprising, in combination, a guide shell, a percussive drilling motor slidably guided and supported by said shell, and yielding resilient feeding means for said drilling motor including a fluid actuated feeding motor, and constantly maintained connections driven by said feeding motor for feeding said drilling motor relative to said shell includ ing a spur toothed rack attached to the inner side of said shell and a spur pinion meshing with said rack and moving at equal rate withsaid drilling motor, said feed motor exerting a constant feeding force on said drilling motor whenever fluid is supplied to said feed motor and permitting free movement of the drilling motor relative to said shell when the supply or fluid to said feeding motor is cut off.

11, A drilling mechanism comprising, in combination, a guide shell, a percussive drilling motor slidably guided and supported by said shell, and yielding resilient feeding means for said drilling motor including a fluid actuated feeding motor carried by and movable with said drilling motor, and constantly maintained connections' driven by said feeding motor for feeding said drilling motor relative to said shell including a spur toothed rack attached to the innerside of said shell and a spur pinion meshing with said rack, said feed motor exerting a constant feeding force on said drilling motor whenever fluid is supplied to said feed motor and permitting free movement of the drilling motor relative to said shell when the supply of fluid to said feeding motor is cut off.

12. A drilling mechanism comprising, in combination, a shell, a percussive drilling motor slidably guided and supported thereby, and means for exerting a yielding feeding pressure on said drilling motor including a fluid actuated feeding motor having motor frame providing bearing means and a rotatable terminal power transmitting element rotatably supported by said bearing means and substantially fixed against longitudinal movement relative to the latter, and power transmitting connections actuated by said element operative on rotation of the latter to impart a feeding force to said drilling motor, and on movement of said drilling motor relative to said shell by extraneous force to transmit rotation to said terminal power transmitting element of the feeding motor.

13. A drilling mechanism comprising a shell, a percussive drilling motor slidably guided and supported thereby, yielding resilient feeding mechanism for said drilling motor including a feed motor having a casing and a power rotor held against axial movement in its casing, and means whereby said feed motor constantly exerts a feeding force on said drilling motor while permitting, and irrespective of movement of the drilling motor.

ELMER G. GARTIN.

CERTlFICATE or CORRECTION.

Patent No. 1,948,518. February 27, 1934.

ELMER G. GARTIN.

It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows: Page 2, line 132, claim 1; for "egaging" read engaging; page 3, line 33, claim 6, after "thereby" insert a comma; line 103, claim 10, for "or" read of;- and line 146, claim 13, before "movement" insert a comma; and that the said Letters Patent should be read with these corrections therein that the same may conform to the record of the case in the Patent Office. I

Signed and sealed this 30th day of October, Av D. 1934.

Leslie Frazer (Seal) Acting Commissioner of Patents. 

